Aniline, a material for rubber chemicals such as antioxidants, thiazole vulcanization accelerators and sulfenamide vulcanization accelerators; and styrene and butadiene, materials for synthetic rubber such as styrene butadiene rubber and butadiene rubber, are generally synthesized from petroleum. However, fossil fuels such as petroleum and natural gas are going to be depleted, and thus a price hike of fossil fuels is expected in the future. For this reason, consumption of fossil fuels has been demanded to be reduced by increasing the yield or substituting biomass resources for fossil fuels.
From the viewpoint of utilization of natural resources, a method of synthesizing a vulcanization accelerator is known in which a naturally-derived long chain amine that is synthesized by reductive amination of a saturated or unsaturated fatty acid obtained by hydrolysis of natural fat and oil is used as a material. However, this synthesis method requires mercaptobenzothiazoles or dibenzothiazolyl disulfide in the production process, and these substances are not taught as products from natural resources.
Examples of known synthesis methods using biomass resources as materials include a method of synthesizing an aromatic compound such as benzene from a lower hydrocarbon such as methane contained in biogas. However, since the material is gas and thus difficult to handle, the method is still desired to be improved. Moreover, a method using biomethanol as a material is also known; but this method is still desired to be improved because of high toxicity of the material. Furthermore, it is difficult for either of the methods to ensure a sufficient yield, and thus improvement is still desired on this point.
Patent Literatures 1 and 2 disclose methods of synthesizing aniline from glucose with microorganisms. However, these methods need some improvement in terms of production speed, production scale or the like, and in terms of usability of various microorganism species, and production efficiency. Therefore, an alternative technique has been demanded.